Hi Hal, The effect is basically a slowdown in case of non responding or lost packets. With 1sec timeout - up to 4sec per lost transaction are added to the SM bringup time.
In many clusters I have seen a 100msec was enough - but I guess you have actually have seen such failures. Eitan Zahavi Design Technology Director Mellanox Technologies LTD Tel:+972-4-9097208 Fax:+972-4-9593245 P.O. Box 586 Yokneam 20692 ISRAEL > -----Original Message----- > From: Hal Rosenstock [mailto:[EMAIL PROTECTED] > Sent: Tuesday, December 20, 2005 3:38 PM > To: Yael Kalka; Eitan Zahavi > Cc: openib-general@openib.org > Subject: [PATCH] OpenSM: Extend default transaction timeout from 100 msec to 1 > second > > OpenSM: Extend default transaction timeout from 100 msec to 1 second. > > With the advent of long distance IB and software SMAs, 100 msec is no > longer adaquete as a default transaction timeout. Increase this to 1 > second which so that the default is sufficient in most common cases. > > Signed-off-by: Hal Rosenstock <[EMAIL PROTECTED]> > > Index: include/opensm/osm_base.h > =================================================================== > --- include/opensm/osm_base.h (revision 4549) > +++ include/opensm/osm_base.h (working copy) > @@ -246,7 +246,7 @@ BEGIN_C_DECLS > * > * SYNOPSIS > */ > -#define OSM_DEFAULT_TRANS_TIMEOUT_MILLISEC 100 > +#define OSM_DEFAULT_TRANS_TIMEOUT_MILLISEC 1000 > /***********/ > > /****d* OpenSM: Base/OSM_DEFAULT_SUBNET_TIMEOUT > Index: opensm/main.c > =================================================================== > --- opensm/main.c (revision 4549) > +++ opensm/main.c (working copy) > @@ -153,7 +153,7 @@ show_usage(void) > " used for transaction timeouts.\n" > " Specifying -t 0 disables timeouts.\n" > " Without -t, OpenSM defaults to a timeout value of\n" > - " 100 milliseconds.\n\n" ); > + " 1 second (1000 milliseconds).\n\n" ); > printf( "-maxsmps <number>\n" > " This option specifies the number of VL15 SMP MADs\n" > " allowed on the wire at any one time.\n" _______________________________________________ openib-general mailing list openib-general@openib.org http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
